Lumbar support pads

ABSTRACT

A lumbar support pad for providing support to a user&#39;&#39;s back by engagement with the small of the user&#39;&#39;s back. The pad is preferably formed from a resilient low density foamed material. The back-engaging surface is complexly curved in a convex direction between the lateral edges and in a concave direction between the longitudinal edges.

baited States ?atent [191 Watkin Oct. 16, 1973 LUMBAR SUPPORT PADS [76] Inventor: Bernard Curtis Watkin, 32 West Square, London, England [22] Filed: June 15,1972

21 Appl. No.: 263,298

[52] US. Ci 297/460, 297/230, 297/454 [51] Int. Cl. A6lg 7/06, A470 7/02, A47c 1/10 [58] Field of Search 297/230, 454-456,

[56] References Cited UNITED STATES PATENTS Radford 297/230 Peras 297/455 3,454,302 7/1969 Radford 297/230 3,555,582 l/l971 Radford... 297/230 X 2,853,122 9/1958 Shapiro 297/230 Primary Examiner-Casmir A. Nunberg Attorney-Neill M. S. Johnston [57] ABSTRACT A lumbar support pad for providing support to a users back by engagement with the small of the users back. The pad is preferably formed from a resilient low density foamed material. The back-engaging surface is complexly curved in a convex direction between the lateral edges and in a concave direction between the longitudinal edges.

8 Claims, 8 Drawing Figures Patented Oct. 16, 1973 FlG.3b

FIGBC LUMBAR SUPPORT PADS This invention relates to lumbar support pads.

According to the invention there is provided a lumbar support pad the support surface of which includes the whole or part of a smooth curve passing through points, the distances of which from a base plane are, at intervals, measured along the base plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00 and 2.00 and 1.50 inches, respectively, 1.15, 1.50, 1.90, 2.08, 2.10, 1.88, 1.48, 0.86, 0.28 inches, the dimensions of the support surface being within i Vs inch of the above-mentioned dimensions.

When the pad is placed in position in the small of the users back, with the smooth curve aligned with the spine and the highest point of the curve next to the fourth lumbar vertebra, the pad is able to provide support for the spine to maintain the lumbar curve of the spine in its correct anatomical position. The smooth curve defined above was found by experimental measurements on human beings and cadavers to be the ideal curve for a support pad suitable for the average person.

Preferably, the support surface of the pad passes through the smooth curve defined above and through further smooth curves on each side of and distant 1.75 inches from the first-mentioned curve measured along the base plane, each of the further smooth curves passing through points the distances from which from the base plane at intervals corresponding to those between points on the first curve are, respectively, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches, the dimensions of the support surface being within i 43 inch of the above-mentioned dimensions.

Advantageously, the support surface is substantially in the shape of the whole or part of a smooth surface passing through points the distances of which from a base plane are, on a first section on a plane perpendicular to the base plane and at intervals measured along the base plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00, 2.00, and 1.50 inches, respectively 1.94, 2.20, 2.50, 2.70, 2.74, 2.60, 2.14, 1.44, 0.78 inches; on a second section on a plane parallel to the plane of the first section and distant from it 1.25 inches, at intervals corresponding to those between points on the first section, 1.74, 2.25, 2.74, 2.88, 2.87, 2.65, 2.22, 1.55, 0.62 inches; on a third section on a plane parallel to the plane of the first section and distant from it 3.00 inches, at intervals corresponding to those between points on the first section, 1.63, 2.00, 2.40, 2.60, 2.65, 2.35, 1.90, 1.24, 0.48 inches; on a fourth section on a plane parallel to the plane of the first section and distant from it 4.75 inches, at intervals corresponding to those between points in the first section, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches; on a fifth section on a plane parallel to the first section and distant from it 6.50 inches, at intervals corresponding to those between points on the first section, 1.15, 1.50, 1.90, 2.08, 2.10, 1.88 1.48, 0.86, 0.28 inches; the smooth surface continuing beyond the fifth section so as to be symmetrical about that section, the dimensions of the support surface being within i inch of the above-mentioned dimensions.

In one form of the invention the lumbar support pad is in the form of a separate cushion having a flat under surface coincident with or parallel to the base plane.

In another form of the invention the pad is formed integrally with another structure, for example, the back rest of a seat.

Suitably, the pad is formed from a low density foamed plastics material.

One embodiment of the invention will now be described by way of example, with reference to the accompanying drawings, in which:

FIG. 1 is a plan view of a lumbar support pad constructed in accordance with the invention;

FIG. 2 is a cross-section on the line 11-11 of the pad of FIG. 1;

FIGS. 3a to 3e are cross-sections taken on lines A-A to EE respectively of the pad of FIG. 1; and

FIG. 4 shows the position of the pad against a users back.

The lumbar support pad 2 shown in the drawings is in the form of a cushion formed from a low density foamed plastics material. The pad 2 has a flat, oblong under surface 4, having longitudinal edges 6 of length 12.25 inches and transverse edges 8 and 9 of length 14.0 inches. In a section taken on a plane A-A perpendicular to the under surface 4, parallel to one of the longitudinal edges 6, the upper surface 10 of the pad appears as a smooth curve, as shown in FIG. 3a. The depth of the pad 2 in this section at a point 12, 0.75 inch from the transverse edge 8 of the pad, measured in the plane of the under surface, is 2.20 inches. At

points 13 to 18 (see FIG. 3), at further consecutive intervals, measured in the plane of the under surface 4 in the direction from edge 8 to edge 9, of 1.25, 1.25, 1.50, 2.00, 2.00 and 2.00 inches the depths of the section are respectively, 2.50, 2.70, 2.74, 2.60, 2.14 and 1.44 inches. In further sections taken on planes B-B to E-E parallel to that of the first-mentioned section the depth of the pad at points the same distances from the transverse edge 8 as the above-mentioned points on the first section are as follows: in a section distant 1.25 inches from the first section, (see FIG. 3b) 2.25, 2.74, 2.88, 2.87, 2.65, 2.22 and 1.55 inches; in a section distant 3.00 inches from the first section, (FIG. 3c).2.00, 2.40, 2.60, 2.65, 2.35, 1.90 and 1.24 inches; in a section distant 4.75 inches from the first section, (FIG. 3d) 1.70, 2.07, 2.24, 2.28, 1.07, 1.60 and 0.96 inches; in a section distant 6.50 inches from the first section, (see FIG. 3e), 1.50, 1.90, 2.08, 2.10, 1.88, 1.48 and 0.86 inches.

The smooth curves thus defined are joined by a smooth surface extending uniformly between the sections, and continuing beyond the last-mentioned section, which is a section through the centre line of the pad, to provide a surface 10 symmetrical about that section.

At the edges 6, 8 and 9 of the pad, the upper surface 10 joins flat side faces 26, 28 and 29 respectively of the pad, perpendicular to the under surface, through smooth curves the radius of which at the transverse edge 8 of the pad is about three-fourths inch, at the transverse edge 9 about three-eighths inch, and at the longitudinal edges 6 a maximum of one-half inch.

The upper surface 10 of the pad 2 is thus curved in two directions; in the direction between the transverse edges 8 and 9 the surface is convex and in the direction between the longitudinal edges 6 the surface is concave.

In the use of the pad 2, it is positioned in the small of the users back as shown in FIG. 4, with the edge 8 at which the thickness of the pad is greatest towards the base of the spine and the thickest part of the central longitudinal section EE of the pad located opposite the vertebra L4, i.e., the fourth lumbar vertebra, the upper surface of the pad engaging the users back. With the pad in this position and the user lying horizontally or sitting on a seat the back-rest of which is inclined at any angle between the horizontal and the vertical, the pad acts as a support for the spine. The effect of the pad is to maintain the lumbar curve of the spine in the correct anatomical position, i.e., with the lumbar vertebra correctly spaced from one another.

The dimensions of the pad given above are preferred dimensions for a pad to be used by the average person, but can be varied to within i inch, the general smooth shape of the upper surface being maintained. The overall dimensions of the pad can be varied to within i 7% inch.

Whilst a support pad in the form of a separate cushion has been described, it will be appreciated that the pad could be formed integrally with another structure, for example, the back rest of an aircraft seat.

What 1 claim is:

1. A lumbar support pad the support surface of which includes the whole or part of a smooth curve passing through points, the distances of which from a base plane are, at intervals measured along the base: plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00, 2.00, and 1.50 inches, respectively, 1.15, 1.50, 1.90, 2.08, 2.10, 1.88, 1.48, 0.86, 0.28 inches, the dimensions of the support surface being within i inch of the above-mentioned dimensions.

2. A pad as claimed in claim 1, in which the support surface passes through further smooth curves on each side of and distant 1.75 inches from the first-mentioned curve measured along the base plane, each of the further smooth curves passing through points the distances from which from the base plane at intervals corresponding to those between points on the first curve are, respectively, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches, the dimensions of the support surface being within i inch of the above-mentioned dimensions.

3. A pad as claimed in claim 2, in which the support surface is substantially in the shape of the whole or part of a smooth surface passing through points the distances of which from a base plane are, on a first section on a plane perpendicular to the base plane and at intervals measured along the base plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00, 2.00, and 1.50 inches, respectively 1.94, 2.20, 2.50, 2.70, 2.74, 2.60, 2.14, 1.44, 0.78 inches; on a second section on a plane parallel to the plane of the first section and distant from it 1.25 inches, at intervals corresponding to those between points on the first section, 1.74, 2.25, 2.74, 2.88, 2.87, 2.65, 2.22, 1.55, 0.62 inches; on a third section on a plane parallel to the plane of the first section and distant from it 3.00 inches, at intervals corresponding to those between points on the first section, 1.63, 2.00, 2.40, 2.60, 2.65, 2.35, 1.90, 1.24, 0.48 inches; on a fourth section on a plane parallel to the plane of the first section and distant from it 4.75 inches, at intervals corresponding to those between points in the first section, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches; on a fifth section on a plane parallel to the first section and distant from it 6.50 inches, at intervals corresponding to those between points on the first section 1.15, 1.50, 1.90, 2.08, 2.10, 1.88, 1.48, 0.86, 0.28 inches; the smooth surface continuing beyond the fifth section so as to be symmetrical about that section, the dimensions of the support surface being within inch of the above-mentioned dimensions.

4. A pad as claimed in claim 1, in which the pad has flat side faces parallel to the plane containing the said smooth curve or curves, and the support surface joins the side faces through smooth curves the radius of curvature of which at the edge of the pad is not greater than one-half inch.

5. A pad as claimed in claim 1, in which the pad has flat side faces perpendicular to the plane containing the said smooth curves and to the base plane, and the support surface joins the side faces through smooth curves the radius of curvature of which at the edge of the pad is between three-eighths inch and three-fourths inch.

6. A pad as claimed in claim 1, in which the pad is formed of a low density foamed plastics.

7. Apad as claimed in claim 1, and in the form of a cushion having a flat under surface parallel to the base plane.

8. A seat having a back rest formed integrally with a lumbar support pad as claimed in claim 1, the pad being positioned so that when a person is sitting on the seat, the support surface engages the person s back and the first-mentioned curve lies in a vertical plane, the end of the curve which is distant 1.15 inches from the base plane being towards the base of the persons spine and the point which is at the greatest distance from the base plane being opposite the fourth lumbar vertebra. =1 1 1 

1. A lumbar support pad the support surface of which includes the whole or part of a smooth curve passing through points, the distances of which from a base plane are, at intervals measured along the base plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00, 2.00, and 1.50 inches, respectively, 1.15, 1.50, 1.90, 2.08, 2.10, 1.88, 1.48, 0.86, 0.28 inches, the dimensions of the support surface being within + OR - 5/8 inch of the above-mentioned dimensions.
 2. A pad as claimed in claim 1, in which the support surface passes through further smooth curves on each side of and distant 1.75 inches from the first-mentioned curve measured along the base plane, each of the further smooth curves passing through points the distances from which from the base plane at intervals corresponding to those between points on the first curve are, respectively, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches, the dimensions of the support surface being within + or - 5/8 inch of the above-mentioned dimensions.
 3. A pad as claimed in claim 2, in which the support surface is substantially in the shape of the whole or part of a smooth surface passing through points the distances of which from a base plane are, on a first section on a plane perpendicular to the base plane and at intervals measured along the base plane of 0.75, 1.25, 1.25, 1.50, 2.00, 2.00, 2.00, and 1.50 inches, respectively 1.94, 2.20, 2.50, 2.70, 2.74, 2.60, 2.14, 1.44, 0.78 inches; on a second section on a plane parallel to the plane of the first section and distant from it 1.25 inches, at intervals corresponding to those between points on the first section, 1.74, 2.25, 2.74, 2.88, 2.87, 2.65, 2.22, 1.55, 0.62 inches; on a third section on a plane parallel to the plane of the first section and distant from it 3.00 inches, at intervals corresponding to those between points on the first section, 1.63, 2.00, 2.40, 2.60, 2.65, 2.35, 1.90, 1.24, 0.48 inches; on a fourth section on a plane parallel to the plane of the first section and distant from it 4.75 inches, at intervals corresponding to those between points in the first section, 1.32, 1.70, 2.07, 2.24, 2.28, 2.07, 1.60, 0.96, 0.35 inches; on a fifth section on a plane parallel to the first section and distant from it 6.50 inches, at intervals corresponding to those between points on the first section 1.15, 1.50, 1.90, 2.08, 2.10, 1.88, 1.48, 0.86, 0.28 inches; the smooth surface continuing beyond the fifth section so as to be symmetrical about that section, the dimensions of the support surface being within + or - 5/8 inch of the above-mentioned dimensions.
 4. A pad as claimed in claim 1, in which the pad has flat side faces parallel to the plane containing the said smooth curve or curves, and the support surface joins the side faces through smooth curves the radius of curvature of which at the edge of the pad is not greater than one-hAlf inch.
 5. A pad as claimed in claim 1, in which the pad has flat side faces perpendicular to the plane containing the said smooth curves and to the base plane, and the support surface joins the side faces through smooth curves the radius of curvature of which at the edge of the pad is between three-eighths inch and three-fourths inch.
 6. A pad as claimed in claim 1, in which the pad is formed of a low density foamed plastics.
 7. A pad as claimed in claim 1, and in the form of a cushion having a flat under surface parallel to the base plane.
 8. A seat having a back rest formed integrally with a lumbar support pad as claimed in claim 1, the pad being positioned so that when a person is sitting on the seat, the support surface engages the person''s back and the first-mentioned curve lies in a vertical plane, the end of the curve which is distant 1.15 inches from the base plane being towards the base of the person''s spine and the point which is at the greatest distance from the base plane being opposite the fourth lumbar vertebra. 